com.persistit

Class KeyState

java.lang.Object

com.persistit.KeyState

All Implemented Interfaces:

Serializable, Comparable

public class KeyState
extends Object
implements Comparable, Serializable

Represent an immutable copy of the state from a Key object suitable for use as the key of a Map.

Version:

1.0

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static KeyState	LEFT_GUARD_KEYSTATE
static KeyState	RIGHT_GUARD_KEYSTATE
static long	serialVersionUID

Constructor Summary

Constructors

Constructor and Description
KeyState(byte[] data)
KeyState(Key key) Construct an immutable KeyState by copying the relevant state information from a Key.

Method Summary

Modifier and Type	Method and Description
int	compareTo(Object obj) Implement Comparable in such a way that Key and KeyState can be used interchangeably as map keys.
void	copyTo(Key key) Copy the content of this KeyState to the supplied Key.
boolean	equals(Object obj) Implement equals in such a way that Key and KeyState can be used interchangeably as map keys.
byte[]	getBytes()
int	hashCode() Compute the hash code for this KeyState.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

serialVersionUID

public static final long serialVersionUID

See Also:

Constant Field Values

LEFT_GUARD_KEYSTATE

public static final KeyState LEFT_GUARD_KEYSTATE

RIGHT_GUARD_KEYSTATE

public static final KeyState RIGHT_GUARD_KEYSTATE

Constructor Detail

KeyState

public KeyState(Key key)

Construct an immutable KeyState by copying the relevant state information from a Key. The hashCode and equals methods of Key and KeyState are compatible so that either a Key or a KeyState may be used as a map key.

Parameters:

key - The Key from which the state is copied.

KeyState

public KeyState(byte[] data)

Method Detail

copyTo

public void copyTo(Key key)

Copy the content of this KeyState to the supplied Key.

Parameters:

key - The key to which content should be copied.

hashCode

public int hashCode()

Compute the hash code for this KeyState. The hashCode is the same as for the equivalent Key, that is the Key from which this KeyState was constructed prior to any subsequent modifications.

Overrides:

hashCode in class Object

Returns:

The hashCode.

equals

public boolean equals(Object obj)

Implement equals in such a way that Key and KeyState can be used interchangeably as map keys.

Overrides:

equals in class Object

Returns:

true if the specified object is either a Key or a KeyState whose state represents an identical object or primitive value.

compareTo

public int compareTo(Object obj)

Implement Comparable in such a way that Key and KeyState can be used interchangeably as map keys.

Specified by:

compareTo in interface Comparable

Returns:

results of comparing the key value represented by this KeyState with a supplied KeyState or Key. The result is negative if this key value preceeds, positive if this key value follows, or zero if this key value is equal to the supplied key value.

Throws:

ClassCastException - if the supplied object is neither a Key nor a KeyState

getBytes

public byte[] getBytes()

toString

public String toString()

Overrides:

toString in class Object